"git clean" does nothing without -f, or the user changing clean.RequireForce=false

"git reset" does nothing irrevocable unless you add --hard (why should you also need to add --force?)

"git checkout" will only trash uncommitted changes if you ask it to specifically. (e.g. 'git checkout <file to overwrite>').

side note: using 'git reset --hard' to teleport a branch around is bad form, imho.